function sgopage()
{
    var form = document.getElementById('spg');
    var pg;
    for (var childItem in form.childNodes)
    {
        if (form.childNodes[childItem].nodeType == 1 && form.childNodes[childItem].id == 'p')
        {
            pg = form.childNodes[childItem];
            break;
        }
    }
    var pgs = document.getElementById('spages');
    var qnum = document.getElementById('spgnum');
    if(!form||!pg||!pgs||!qnum) return;
    var pgsa = pgs.value.split(',');
    qnum = parseInt(qnum.value);
    if(isNaN(qnum) || qnum > pgsa.length - 1 || qnum < 1) return;
    pg.value = pgsa[qnum-1];
    form.submit();
}